Ink delivery systems are utilized by various types of printers to generate text and/or images onto a printing medium, such as paper, normally in response to communications from a computer. One particular type of ink delivery system is known as an ink jet system. Ink jet systems typically utilize cartridges as a means of storing and delivering multiple colors of ink. The cartridge typically includes a reservoir for holding a supply of ink and a printhead for depositing ink on the paper. The cartridges are located inside the printer and are configured to travel from side to side on a shaft to deposit ink on paper as dictated by the computer. The location of the entire ink jet cartridge on the shaft is known as being “on-axis.”
Typically, once one of the colors is exhausted, the entire cartridge is replaced with a new cartridge. The replacement of the entire cartridge can be inefficient for at least two reasons. First, the entire print cartridge requires replacement, though only one specific color has been exhausted while the remaining colors may have sufficient ink levels for further printing. Second, although a particular color has been exhausted, the printhead is still operational, yet it is disposed of with the rest of the cartridge because, typically, an end user cannot replace an ink supply alone, without replacing printheads. These inefficiencies can lead to large expenses and waste for users of the ink jet cartridge systems. Improved ink delivery systems have been developed to alleviate the need to replace an entire multiple color ink jet cartridge, including the printhead, after a single color had been exhausted.
In an improved ink delivery system, the actual supply of the different ink colors may be located off the printer shaft, i.e., “off-axis.” Only a relatively small local ink reservoir and the printhead are located on-axis. Each color has its own off-axis supply of ink. The separate ink supplies allow for the replacement of a particular color after being exhausted rather than having to unnecessarily replace an entire cartridge that has not been completely depleted or replace printheads that are still operational.
While the improved ink delivery systems allow users to replace ink supplies that have been depleted, users typically must do so with the same type and color of ink. The same type and color must be used because printhead assemblies cannot be adequately purged and cleansed of one color and type of ink in preparation for a different color and type of ink.
The embodiments described hereinafter were developed in light of this situation and the drawbacks associated with existing systems.